A Question About Time Travel & Aging

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Discussion Overview

The discussion centers around the implications of time travel on aging and identity, exploring hypothetical scenarios involving time travel, paradoxes, and the nature of existence. Participants engage with concepts related to time dilation, the potential for multiple versions of oneself, and the philosophical ramifications of returning to a point in time.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants propose that if one travels back in time and lives for four years, they would age four years regardless of the time elapsed for others.
  • Others argue that returning to a point in time shortly before departure creates a paradox, as two versions of the same person would exist simultaneously.
  • A participant suggests that both versions of a person could be considered "real," challenging the notion of additional matter being created in this scenario.
  • Another viewpoint emphasizes the need to conceptualize objects as four-dimensional structures, where their passage through time is integral to their identity.
  • Some participants express confusion over the implications of returning to a point before departure, questioning the nature of choice and existence in such a scenario.
  • There are discussions about the potential consequences of repeated time travel, including the idea that it could lead to a black hole if enough cycles occur.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the implications of time travel, particularly concerning aging, identity, and the existence of paradoxes. The discussion remains unresolved, with no consensus reached on the nature of these issues.

Contextual Notes

Limitations include the reliance on hypothetical scenarios and the ambiguity surrounding definitions of identity and existence in the context of time travel. Unresolved assumptions about the mechanics of time travel and its effects on aging are present.

asesena
Let's assume time travel is possible and we are travelling. We jumped to a TARDIS sort of machine in August 26, 2017 and go to August 26, 2000 then lived there for 4 years until August 26, 2004. So when we come back to August 26, 2017 would we be 4 years older or be the same age we were before travelling?

I know it is kind of a lame question but that'd be amazing if you answered this.Thank you already [emoji68]‍[emoji436][emoji177]
 
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You would still have aged 4 years from 2000-2004. Even with "real" scientifically proven time-dilation effects the difference in years elapsed is relative to other observers with their clocks ticking at different rates, when you have a clock/calendar with you that says a year passed you age a year, even if someone else's clock says 10 years passed for them and they are 10 years older...
 
This involves one of the paradoxes involved with the idea of reverse time travel, which hint that it cannot actually be possible.
Suppose that after your 4 year stint away from base, you return to just a few minutes before you originally left.
Now there will be two of you in the same place, one being four years older than the other.
Which one is the 'real' you, and where did the additional matter come from which makes the other copy of you?
 
rootone said:
This involves one of the paradoxes involved with the idea of reverse time travel, which hint that it cannot actually be possible.
Suppose that after your 4 year stint away from base, you return to just a few minutes before you originally left.
Now there will be two of you in the same place, one being four years older than the other.
Which one is the 'real' you, and where did the additional matter come from which makes the other copy of you?

Those aren't paradoxes. They are both the "real" you, and there isn't any extra matter, you are counting the same matter twice.
 
Algr said:
Those aren't paradoxes. They are both the "real" you, and there isn't any extra matter, you are counting the same matter twice.
That doesn't make any sense to me. If you could return to a point on a timeline shortly before you left there would be two of you and two machines that you used to "transport" through time existing in one time up until the time you originally left.
 
Screen Shot 2017-08-26 at 4.08.14 PM.png


It's like this. The string appears three times along the blue line. But it is only one string.
 
In the bars above the "have something to add?" box there is a picture next to the smiley face...
 
But that only let's me input a URL, not upload a pic I just made. I found what I needed by editing the post.
 
Algr said:
It's like this. The string appears three times along the blue line. But it is only one string.
I see says the blind man to the deaf ears.
I thought about virtual existence AKA virtual particles when I wrote my response. Very big "IF" you could borrow matter from the future briefly and deposit it in a time before you took it, it would all balance out... very big if.
 
  • #10
It isn't virtual. You need to think of the object as a 4 dimensional structure. It's passage through time is part of it's identity. A time machine allows the strings personal timeline to travel contrary to an external viewer's timeline. The paradox doesn't start unless the future timeline somehow contradicts what it's own time did.
 
  • #11
Algr said:
Those aren't paradoxes. They are both the "real" you, and there isn't any extra matter, you are counting the same matter twice.
If you only count it once there still is a problem.
If you having returned you decide not to do that trip?
 
Last edited:
  • #12
rootone said:
If you only count it once there still is a problem.
If you having returned you decide not to do that trip?
Or if you still want to do the trip. Enough cycles will collapse into black hole.
 
  • #13
rootone said:
If you having returned you decide not to do that trip?

The fact that you returned proves that you do/did (there is no difference) the trip. There is no choice anymore.
 
  • #14
Then it becomes impossible for you to have had a life which lead to your original decision to do it.
 
  • #15
rootone said:
Then it becomes impossible for you to have had a life which lead to your original decision to do it.

I think you mean it is impossible to have had a life that doesn't lead to the original decision to do it. Everything else makes no sense.
 

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